Electric stop motion for double feed mechanism on knitting machines



R. HILL 2,531,681 ELECTRIC STOP MOTION FOR DOUBLE FEED MECHANISM 0N KNITTING MACHINES Nov. 28, 1950 Filed July 14, 1949 2 Sheets-Sheet l FIE-1.

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0 cd ms 9.1%,. 29 0 wail Nov. 28, 1950 Filed July 14, 1949 "&

' R. HILL ELECTRIC STOP MOTIGN FOR DOUBLE FEED MECHANISM ON KNITTING MACHINES 2 Sheets-Sheet 2 FIE-El.

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In r enfor Roscoe Hi// Patented Nov. 28, 1950 ELECTRIC STOP MOTION FOR DOUBLE FEED; ECHANJS M ON MA.-

ltoscoe -Hi;ll-,-Hamilto n, Ontario, Canada, assignor to sew '& "williains .l ee e e: ee e Application Jyly, 14-,?1949, ezgigtl 124,793 a Qlairns ((166-157) ble-feed d etteehment so th t W ewes ii'ele cie .eenibelni tedeeeh orevelu hn .Q th mar.

chin in placev ,o a. ine s n eere k b e. mac in withq todei b e e e Th .el ibl fee i ,ee oxnpl shedoby intrqdq tee .a se ed yer et e e 9nd.f ed int at t e efe ef-t e" meehine en th neck e m y t e mad .t i twee he .hee and tee Wher snittirief ttiie, e ntmuetee tsn ed men pel t ,nee e ehll h r h ed. le e re e ei tu diein he z eit ee .o th -hee ee te th texlin l iee reeete an nl s 1 79.- vie'qn' is mete I9 e s ding k n er th second ,tfees v oi t .sleme o t mew-h v il cu resu tin both h ex ens v e aint Q thetslemeg end th .q nsesi e ss. o reduction until the damage is repaired.

A99Q C iin yr9n exi tin eeh ne mean see eedie lke iim tthe ee n t eedi i te e nclud in the dq lele e ettee mentens peree n l ir neem on the m inv e wette mmd itteme hine F om exn tiei eeit-he een elled ha v double feed control mechanism isliable come out of time or synchronism with the re rna inger of thein'achine and upon such occurrenoelgnitting at the secon'd f eed point is' not suspended and commenced at the nropentirne, With-the'respltthat-feeding at the second point during -knitting of the heel or toe where the needle cylinders are reciprocating may occur and damage-to the machine and loss of production as explaineel above is apt-to result;

It is the object of-this invention to provide a stop motion associated with the flouble f eed attachment to aocurately determine whether or not the douple-feed mechanism and the machine are in synehronism and to stopthe' maohine upon the ciofible teed mechanism becoming ont of-time" with the knitting action to overcome the previously enopuntered d i fiiculty.

eee eim e 9 di f rent" Ji in; .z th ,eeeetd ee is esigned t cylining eneehme er n te provi w t goo 2 et eeet meeh e e ed with ieen ent e e el gt qng wi hout m difies-0 a ter.- Wete e wi h th t e nt meehmee "The principal feature of the invention consists li rt m' i e e eemu e e eh cni h fei y a notc .giisomgu'nted onthe'yeftical shaftof h se. a "m et ,Qff 'h d uhlei e e fiec i- P1 3 ele with th hHel Te m e e n tiie ca feeders and (trappers of the extra feed,

ea 'w' t'eh eqnne te inthemach ne te 'n zo rui h be opera ed by. th it lupq th reeki f emehen smp o xir. 2 etenerfim ekine'ffir t dine e eem e i time r l te t9 the .dQllb ede id ,j 28 fil' r w the 'e jm .sw ft'e a so coilie eo t e mach n i t'oi mo on con rol cirl i en i Ser e wit the 'afore e ,ewitch w bi fih the double t e p t e meeha m ebin -1 St 011 the se ond switch .eperet eb th gye nt' l 1'1' coiii idente lw th the operation of itl iei firs t switch the notched disc r p on oo nl ple'tion of the movement of the leeb e'i ee 'g eeki eim e eeie t nte e d top .Q n 91 ci cu t ode-ene gize to ere.- etit t l i l l hemeeh n i .r f ?e to th 'eee m en ned ew n s F ij an eleve qne iew 'o dou le eejid i eit'ien F u an a i eem ntery plan sec io a ew illii 'stfatiing the manner in" hichithe v double feed iiifianisni is racked as controlled .the. main c ontrol qrum of themaohine.

QFigiui: 3" isa' circuit diagram of the normal ellectric'stopdnotioncontrol eircnit of alinitting machine which double feed attachment stopilnotionhasbeen incorborate'ol. I

Figures 4, send 6 tie (iiajgrainmatic illustrations' showing successive movements :of the Another important object is to proVide' a stop inotion gevice including an electrical control iroqit whieh can lee-readily incorporated.- into an exei e ele triel it n wee q t epieea etime; e eupenpbr ekeeeq e r m e eeee keeeee fa fidres.

A til the "im t nt obfieet l n iet fi nmviq i op 3G 91? e e e j -ihfih we e eeeil eei l ll fltei i eee iee l .eeeeted e9 Figures 'l, 8 and 9 are diagrammatic illustra tions "showing the successiiiebositions of the main controfdruifi ooiresponding to the positions of the'donh'le fed 'nothec'l' disc yvi th the control we e ee ,ee i eeeeeee in time synohronisml I In reference to thed rawings, only tho separts inachine is controlledthrough'cam mechanisms arrangedpn the main or front control; drum Ki ls is wellfnn'derstood 'i'n'the' art' Ehplouble feed :at'taohfnent generally jles lgna'tegi as 2 comprises a terticalpifac'li'etiijm"tinted e "t e treme 4 9 the thyl? E'Ktetdme 3 through thi bracket 3 is a vertical shaft 5 on the upper end of which are secured the double feed operating cams 6 which operate respectively the draw thread trapper, the double feed trapper, the

double feed feeder, the plain and rib feed bolts and the draw thread feeder mechanisms, details of which are not shown.

i oft the periphery of the rack wheel.

Secured to the lower end of the vertical shaft.

5 is the horizontally disposed rack wheel'l carrying the peripheral pins 8 with which the racking pawl 9 co-operates and provided with the peripheral notches It with which the prop lever co- Thus it will be seen that racking is initiated by the main or front control drum l but once I initiated racking continues as controlled by the operates to control the racking of the rack wheel,

as hereinafter explained:

- Mounted on the front control drum l are cams |2 (only one being shown) which are arranged to operate the double feed attachment at the points in the article to be knitted where it is necessary to bring the double feed into operation or to suspend the double feed action.

When the front drum is racked through the normal operation of the machine to the point where the double feed mechanism is to be actuated, e. g., going into the knitting of the heel or toe of the sock, cam l2 engages the springloaded push rod |3 to move same horizontally against the restraining action of the spring 14. This push rod in turn rocks the shaft l5 through the lever |6 and the spring H which is compressed between the lever I6 and the abutment H! on the push rod I3 as the push rod is forced rearwardly.

Mounted on the shaft I5 is an arm l9 carrying at its upper end a journal boss in which slidably operates a racking push rod 2| which is swung upon rocking of the shaft [5 into co-operative relation with the racking cams 22 mounted on the bevel gear 23* of the machine.

The racking cam 22 (being actually two diametrically opposed cams) is formed with its cam surface on its forward peripheral face. The racking push rod 2| enters the path of this cam surface through one of the openings 24 so that the timing between the movements of the racking push rod 2| and the machine will be synchronized.

The spring I1, which has been compressed during the movement of the racking cam '22 to permit entry of the racking push rod, serves to force the push rod into position as an opening 24 comes opposite thereto.

Also mounted on the shaft [5 is an arm 25 which is normally forward of the rearward endof the prop lever H but which, when swung rearwardly as the shaft I5 is rocked to move the racking push rod 2| into the path of a racking cam, clears the prop lever II to permit the latter when swung on its support 26 to block the return movement of the arm 25 and shaft I5 to withdraw the racking push rod 2| from the racking cam 22.

With the racking push rod in position to be engaged by a racking cam it will be forced outwardly in its boss 20 to engage the end of the racking pawl lever 2! which operates the racking pawl engaging the pins 8 of the racking wheel to advance the wheel in steps to rotate the vertical shaft 5. 5

, Normally when the racking wheel 1 is at rest the end of the prop lever II which carries the foot '28 engages in one of the peripheral notches IU of the rack wheel, but upon the wheel being racked its foot rides out onto the periphery of the rack wheel to swing its opposite end into the path of the arm 25 which has been cleared there from upon rocking of the shaft |5 to position the racking push rod 2| in the path of a cam 22.

" Thus the racking push rod 2| will be held from,

prop lever H and spacing of the peripheral notches l0 on the rack wheel.

Once racking has been initiated a proper racking operation must be relied upon to maintain the double feed attachment in time or synchronism with the machine. It has been found in practice however that due to improper lubrication or improper action in any phase of the mechanical movement effecting racking of the rack wheel 1 the'double feed mechanism may become out of time with the remainder of the machine and the cams 6 will not operate to introduce or withdraw the knitting cams at the second feed point at the correct instant, resulting in the damage described above. This fact is particularly true where the extra feed is taken out of action at the heel or the. toe at which points the movement of the rack wheel 1 is very rapid and due to the speed of racking the wheel may overthrow and move beyond its normal osition, preventing in some cases the prop lever H from falling into the notch l0 prepared therefor.

My control device to actuate the stop motion of the machine upon such loss of timing between the double feed attachment and the machine comprises the cam device in the form of a notched disc 25 located on the vertical shaft 5 of the double feed attachment and arranged to operate the switch 30, and a cam 3| mounted on the front control drum l and arranged to operate the switch 32, the switches being included in the stop motion control circuit of the machine shown in Figure 3.

The notched disc 29 on the shaft 5 normally holds the switch 30 in the closed position, as shown in diagrammatic form in Figure 4, which illustrates the relationship of the disc and the switch at the instant racking is initiated to withdraw the extra feed and take it out of action at either the heel or the toe.

Formed in the periphery of the disc 29 is a notch 33 which, when brought opposite the spring contact arm 34 of the switch 30, allows the arm 34 to move away from its co-operating contact 3-5 to open the switch 30 upon moving into the notch.

In taking the extra feed out of action at the heel for instance two very sharp rapid racks occur. Figure 5 shows the relationship of the notched disc 29 and the switch 30 following one rack. It will be seen that the switch 3|] is still maintained in the closed position. Upon the second rack the disc 29 will be further rotated corresponding to the movement of the rack wheel I and vertical shaft 5 operated thereby, and the spring contact arm 34 registers with and moves into the notch 33 to open the switch 30.

. On the other hand, it will be seen from Figure 7 that the switch 32 is normally open, Figure '7 illustrating the relationship between the cam 3| on the control drum l and the switch 32 at the instant racking is being initiated corresponding to the illustration of Figure 4.

Upon the initial rack, Figure 8, which corresponds to Figure 5, shows the second switch 32 so related. to the front control drum cam 3| that casement;

itsacontacts-fifi and 3T1arexstillrmaintainedzin the: open: position... Uponithessecond'rack it-Will --;b'e-= seen that the-"cam? 32: has;movedi to;.closea the" contactsitt's'and 37, and: asithe; timing sequence of "Figure 9. corresponds i tothe *tim-ingxsequence ofJLFigure-JG it"will "be seenvthat this switch 132" is closedz-an instantiafter the switch. 30" is 'opened,: withi thermachine contrcl drum. I and .doublefieed attachment:2 inzsynchronism.

shouldizthesrackdwheel i a overrethrowaor should itnot :be-i racked -far' enough through sticking of one of the racking pawl operators described:

above; itta-will F benseen :thatthe2notch 33 of r the dis'c 29.: willznot J register withutheirendizof the spring. contacttarm t l at thercompletion.oftthe... racking; operation and; thezswitch 30. will be maintained. closed at theitimecthatwthe contacts'i 36and 3iof the secondxswitch. 32 are closediby the :cam' 3 i With referencetoFigure:-3;.it will 'be seen that. thew-switches 305 and 32 are connected." in series: between the. liver: conductor 38 of the: electric stopmotion control circuitof theimachineigener ally designated :asi 39 and ground. Thisiconn'ec tion: placesi the. switchesin series in a normally open l circuit with an electi e-magnetic operator 41 which when energized: by the closing of switchesttcandtzoperates'a device (not shown) which mechanically stops;th'e knitting machine.

Aisozincluded in series: with this unit the stop moti'on machine circuit are the usual top tension dropper switch 42,1 dropper switches 43 andineedledetectorswitches; all of which form r.

circuits: paralleling the series switciocstn and 321 Itlwillfbe seen'thatas long:asat least one of-the-iswitches 30 and 32- remains open there will be no current fi'owthro-ugh the circuit branch in cluding theaswitch'esto energize thecoilbi M to stop the machine.- These switches 36" and 32" will always maintain: the stop motion control circuit 39 dle-energized "with one of" the switches" contacts beingopen atall times with'the double" f ed attachment and the machine in synchro nism; as :cle'arly shown inFigures 4 to 9 How ever, should the double feed mechanism lose step Withthemachine; either'through failure to rack or: through "the racks overthrowing, the switch 30 will'be :closed when the cam 31 on the maincontrol drumaffects the closing of the switch 32.

With the concurrent closing of these two switches a the: coil 1 operator 4 I will 1 be energized and t the mechanism operated to stop the machine.

It will be'seenthat the'inclusion of 'these two' switches stand 32' into the electric stop motion controlcir-cuit 39 of the machine will not interfere inan'y way with theoperation-of this circuit throughthe action of the top tension dropper' switch '42," dropper switches 4-3'or needle detector switches 44, which operate in the usual manner,

asiwelltknown in the 1 art, to stop the machine. 6

While: the diagrammatic illustrations of Fig-* ures'4 to'9 show the disc -29 provided withthe' singlenotch 33 and the front control drum l providedr with thesingle'cam projection 3 l it. 'will" be appreciated "that -several notches may bein= cludedin the surface of the disc 29 and several cam" projectionson the drum l to control the synchronism of the machineat-the'various points where it is desired or required to introduce or withdraw the double feed'attachment, Figures 4 to 9 being by way of illustration only;

The modification? of present machines equipped with conventional electric stop motions to include mycsafety, control feature is extremely; simple; Thesnotched; disc 29 is simply'zmountedromthe r 6 vertical I shaft 5 i and thencam '3l mounted on aconvenientsegment: of.. the control drum: I I and' i adjusted relative to their" respective switches 30' and 32 to gain their relationships illustrated in Figures 4': to 9; Once these'cam's andiswitoheshave been" relatively located they are securely locked v in position and 1 the switches included -in the stop motion :controlcircuit of the machine; The provision of the: notched" disc, cams and switches-will stop the machine upon anyim manner. to be moved-or driven'in synchronism" with the knitting action of'the machine without departing from the scope'of my invention; The-'- only? stipulation which-must essentially be 'fulfilled isthat it'must functionto' close'its nor-- mally open switch 32 an instant after the nor- 1 mally closed switch 36' is opened 'upon anormal racking of the double feed mechanism;

While my device ha been described as beingappli'ed to :a knittingmachine presently equipped WithJan electric stop motion; itsh'ouldbe 'understoodlthat, variouselectric stop motions are com mercially availableifor use" on-machines'not soequipped'and uponapplication'of one of these; my devicecould'beinstalled to function'as de- .scribed.' It should also be understood that by combining'my device with a suitable'transformei" andan electro magnet to trip the machine stop mechanism, it would operate independently of 1 any other stopmotion.

What I claim as my invention is:

1. In a knittingmachine equipped for double feed,..v the' combination with the main" control" drum, the double feed mechanism including rack-'- ing wheel and cam'operating'vertical shaft oper rated thereby, and mechanism for efiecting the rackingof'said-double feed mechanism into and outof-feeding'relation upon actuation of said' control drum, ofa'notcheddi'sc mounted on 'said'- cam operating shaft; a stop motion electrical control circuit, a' switch included in saidbontrol circuit and" arrangedadjacent said notched disc to be operated thereby upon completion of nor mal racking of "said." double feed mechanism; a 1 cam located on said" main drum and. a second zswitch included: in said" stop" motion electrical control circuit and arranged adjacent saidcami to be actuated therebycoincident with the completion ofthe normal racking of said: doublefeed mechanism-said switches being connectedin series to maintain said stop motion": electrical control circuit" de-energiz'ed'while said'rackingc mechanism and control drurrrremain in synchro 1 nism and-to energize said electrical control cin cuit uponsaidracking, mechanism and" control drum moving out 10f synchronism during. racking tostopsaidmachine;

2; In aiknittingimachine equipped for=-doub1e: feed,thecombination with-the main control drum, the double :5f96d. mechanismincluding a racking,

wheel and :acam roperating'shai-t secured ithereto accuserfor effecting the introduction and withdrawal of asecond yarn for commencing and ending double feed, mechanism actuated by said control drum for operating said double feed mechanism, and a stop motion electrical control circuit to stop said machine upon energization, of cam means mounted on said shaft to be racked with said rackin wheel, a switch included in said control circuit and arranged adjacent said shaft to be'operated by; said cam means at the end of normal rack of said racking wheel to actuate said double feed mechanism; a second cam mounted on said main drum, a second switch mounted adjacent said main drum to be actuated by said second cam means upon the movement of said main drum to a position corresponding to the position which said rack wheel has been moved at the end of its rack when in correct synchronized relationship with said main drum, said switches being connected in series with one switch normally open and the other normally closed to maintain said control, circuit ole-energized and coincidentally closing and opening respectively with said main drum and racking wheel moved in correct synchronized relation but adapted to both assume a closed position upon said drum and racking wheel losing synchronism.

3. A device as claimed in claim 2 in which said switch operated by said cam means mounted on the shaft of said double feed mechanism is normally closed and said second switch operated by the cam means on said main drum is normally open.

4..In a knitting machine equipped for double feed, the combination with the main control drum, the double feed mechanism having a racking wheel to effect upon being racked the introduction and withdrawal of yarn at the second feed point for commencing and ending double feed, a mechanism controlled by the main drum for racking said double feed mechanism in synchronism with said main drum to suspend double feed at the heel and toe, of means for stopping the machine upon said main drum and double feed racking wheel losing synchronism during the racking of said racking wheelto suspend knitting at the heel and toe, said means comprising a notched disc driven by said racking wheel, a normally closed switch arranged adjacent said notched disc to be opened thereby upon said racking wheel completing a normal racking movement to withdraw said double feed mechanism, a cam driven by said main drum, a second normally open switch arranged to be closed by said cam an instant after opening of the first switch with said racking wheel and main drum in synchronism, and a stop motion control circuit having said switches in series included therein to be energized thereby upon said racking wheel and main drum losing synchronism to effect the closure of said switches at the same time.

5. In a knitting machine equipped for double feed, the combination with the main control drum, the double feed mechanism having a racking wheel to effect upon being racked the introduction and withdrawal of yarn at the second feed point for commencing and ending double feed, a mechanism controlled by the main drum for racking said doublefeed racking wheel in synchronism with. said main drum to suspend double feed at the heel and toe, of means for' lstoppingthe machine'upon said main drum and racking wheel losing synchronism during racking of said racking wheel, said means comprising anormally de-energized control circuit to stop the machine upon energization, a normally" closed switch and a normally open switch connected in seriesrin said control circuit and arranged to energize same upon being closed, a notched disc driven by said racking wheel to open said normally closed switch upon completion of normal movement of said racking wheel, and a cam driven by said main drum to close said-normally open switch an instant after said normally closed switch is open with said racking wheel and main drum in synchronism to maintain said control circuit de-energized.

6. In a knitting machine equipped for double feed, the combination with the main control drum, the double feed mechanism having a racking wheel to effect upon being racked the introduction and withdrawal of yarn at the second feed point for commencing and ending double feed, a mechanism controlled by the main drum for racking said double feed racking wheel in synchronism with said main drum to suspend double feed at the heel and toe, of means for stopping the machine uponsaid main drum and racking wheel losing synchronism during racking of said racking wheel, said means comprising a normally de-energized control circuit to stop the machine upon energization, a normally closed switch and a normally open switch connected in series in said control circuit and arranged to energize same upon both being closed, means actuated by said double feed mechanism to open said normally closed switch upon completion of a normal rack and arranged to maintain said normally closed switch closed upon improper racking of said double feed mechanism,

and means actuated by the machine to close said normally open switch an instant after said normally closed switch is opened upon normal racking of said double feed mechanism.

7. In a knitting machine equipped for double feed, the combination with the main control drum, the double feed mechanism having a racking wheel to effect upon being racked the introduction and withdrawal of yarn at the second feed point for commencing and ending double feed, a mechanism controlled by the main drum for racking said double feed racking wheel in synchronism with said main drum to suspend double feed at the heel and toe, of means for stopping the machine upon said main drum and racking wheel losing synch-onism during racking of said racking wheel, said means comprising a normally de-energized control circuit to stop the machine upon energization, a normally closed switch and a normally open switch connected in series in said control circuit and arranged to energize same upon both being closed, cam means driven by said racking wheel to open said normally closed switch upon completion of normal movement of said racking wheel, and cam means driven in synchronism with the knitting action of said machine to close said normally open switch an instant after said normally closed switch is opened with said racking wheel completing a normal racking movement.

ROSCOE HILL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

